Control for supercharged internalcombustion engines



y 1949. c. H. RIDGLEY ETAL 2,476,063

CONTROL FOR SUPERCHARGED INTERNAL-COMBUSTION ENGINES Filed Jan. 17, 19442 Sheets-Sheet 1 Inventors: Cha'rles HRidQleg, Francis W. Trgesdell,Herbert HAnder'sen,

by WW 244411 Their- Attorney.

July 12, 1949. c RlDGLEY ETAL 2,476,063

CONTROL FOR SUPERCHARGED INTERNAL-COMBUSTION ENGINES Filed Jan. 17, 19442 Sheets-Sheet 2 Fig. 2.

Fig. 4.

Inventors: Charles H. Hidgley, Francis W. Truesdell,

Herbert H. Andersen,

Their Attorney.

Patented July 12, 1949 CONTROL FOR SUPERCHARGED INTERNAL- COMBUSTIONENGINES Charles H. Rldgley, Marblehead, and Herbert H. Andersen,Beverly, Mass., and Francis W. Truesdell, Schenectady, N. Y., assignorsto General Electric Company, a corporation of New York ApplicationJanuary 17, 1944, Serial No. 518,568

33 Claims. (01. 170-13513) The present invention relates to control forsupercharged internal combustion engines. It is especially applicable toaircraft engines and it is this application of the invention which hasbeen elected specifically for illustration and description. It is to beunderstood, however, that the invention, especially as to certainaspects, is not limited thereto but may be used wherever foundapplicable.

The object of theinvention is to provide an improved control of the typereferred to, and for a consideration of what is believed to be novel andthe invention, attention is directed to the following specification andto the claims appended thereto. I

In the drawing, Fig. 1 is a diagrammatic view of a supercharged aircraftinternal combustion engine provided with a control embodying theinvention; Fig. 2 is a detail view on a larger scale of parts shown inFig. 1; Fig. 3 is a detail view of certain parts; Fig. 4 is a detailview of a modification, and Fig. 5 is a detail view of a furthermodification.

Referring to the drawing, i indicates an aircraft engine, an engine ofthe radial type being indicated, which drives an aircraft propeller 2.The intake pipes are indicated at 3. They serve to convey fuel mixturefrom a manifold 4 to the respective cylinders of the engine. Manifold 4may be on the discharge side of and form a part of a supercharger driventhrough gearing from the engine shaft. The carburetor for the engine isindicated at 5. Its discharge side is connected to the engine by a pipe6. Its inlet is connected by a pipe line I to the discharge side 3 ofthe compressor 3 of a supercharger, a compressor of the centrifugal typebeing shown. In pipe line i, there may be arranged a known form oflntercooler In for cooling the air discharged from compressor 9 on itsway to the carburetor. In the interest of cleamess, the intermediateportion of pipe line i has been omitted. The air inlet of compressor 9is shown at II. It ma convey air from the aircraft slipstream to theinlet of the compressor, its inlet end, in known manner, facing into theslipstream so that when the aircraft is moving, air is rammed throughconduit II to the compressor inlet. Thus the air supplied to thecompressor inlet will be at a pressure higher than ambient pressure byan amount depending upon the speed of the aircraft. The pressure at thecompressor inlet is termed usually the ram pressure.

Flow of fuel mixture at the carburetor is controlled by a usual form ofthrottle valve l2 on y, fixed on a shaft 29.

wheel at 2i.

the spindle of which is an actuating arm II connected by a link I4 to anarm i5 fixed on a shaft i8. Shaft I6 may be carried in suitablebearings, not shown.

In the present instance a supercharger of the exhaust gas driven turbinetype, termed a turbosupercharger, is illustrated. Exhaust conduit I! ofengine i is connected to the inlet is of the nozzle box is of the gasturbine which forms a part of the turbosupercharger. The nozzles of thegas turbine are indicated at 20 and the turbine Connected with nozzlebox is is a waste conduit 22 in which is located a waste valve 23. Valve23 is carried on a suitable spindle on one end of which is an arm 24through which valve 23 is moved. The operation of a turbosupercharger ofthe type illustrated is known. When waste gate valve 23 is fully open,as indicated in the drawing, substantially all the gases conveyed to thenozzle box discharge directly to atmosphere, little if any beingdirected through the nozzles against the turbine wheel. This representsa condition of no load on the turbosupercharger. As waste gate valve 23is gradually closed, fewer gases escape through waste conduit 22directly to atmosphere and more and more of the gases are directedthrough the nozzles to the turbine wheel, thus building up the speed ofthe turbosupercharger. As waste gate valve 23 is gradually closed, thepressure in the nozzle box is increased as is well understood. Maximumspeed of the turbosupercharger is reached when waste gate valve 23 isfully closed, all the exhaust gases being then directed against theturbine wheel. The turbosupercharger illustrated is to be taken astypical of any suitable type of supercharger.

Fixed on shaft is is an arm 25 connected by a link 26 to one end of alever 21 pivoted at an intermediate point on the end of an arm 23 Theother end of lever 21 is connected by a link 30 to the outer end of anarm 3| fixed on a shaft 32. Shafts 29 and 32 are mounted in suitablebearings, not shown. Arm 3| is connected by a link 33 to one arm 34 of abell crank lever fixed at its elbow on a shaft 35 which shaft is mountedin suitable bearings, not shown. The other arm 36 of the bell cranklever is connected by a link 31 to a pilot control lever 38 pivoted on afixed support 39 and having an operating ball 40 at its free end. Fixedon shaft 35 is a cam 4i having a cam slot 42 in which rides a pin on theend of one arm 43 of a bell crank lever which is pivoted at its elbow ona suitable support and has its other arm 44 connected by a rod 45, abell crank lever 46 and-a rod 41 to the operating arm 48 used to adjustthe speed setting of the propeller governor 49 which controls the pitchof propeller 2 which in turn controls the engine speed. 1

With the foregoing arrangement, the pilot by movingcontrol lever 88 canadjust simultaneously the throtie valve II of the carburetor and thesetting of the propeller governor 49. When the upper end of controllever 38 is moved toward the left, shaft is is turned through thelinkage mechanism in a direction to open the throttle valve. At the sametime, cam 4| is moved in a direction to set the propeller governor forthe engine speed desired for the particular throttle opening. When theupper end of control lever 38 is moved toward the right, shaft I8 isturned in a direction to move throttle valve l2 toward closed position,and simultaneously move cam 4| in a direction to set the propellergovernor for the engine speed corresponding to the new control leverposition; Thus, it will be seen that by means of control lever 88, thepilot can simultaneously adjust mechanically bydirect connections boththe throttle valve and the propeller governor. Arm 28 and shaft 29 arebiased toward a position wherein arm 28 engages a stop 49* by a suitablespring 49. In other words, spring 49 tends to move arm 28 in a directionto efiect a closing movement of throttle valve l2.

Rod 45 is provided with means whereby at any time it may be locked in anadjusted position thus locking the propeller governor in the position atv which it is then set. To this end, it is shown as being provided withteeth 45 which form a rack adapted to be engaged by teeth on a lockinghead 45 carried by the plunger of an electromagnet 45. When the windingof electromagnet 45 is energized, movement of its plunger brings theteeth on locking head 45 into engagement with teeth 45 to lock rod 45 inthe position it occupies at the time. Locking rod 45 in a fixed positionserves to lock the propeller governor in a fixed position. To permit ofcontinued movement of pilot control lever 88 after rod 45 is locked in afixed position, a yielding link is provided in the present instance bymaking rod 45 in two sections connected by telescoping sliding memberscomprising a casing 45 fixed to one rod end and a head 45 fixed on theother rod end and slidor power output of the engine. Preferably it isunder control of and responsive to the pressure on the discharge side ofthe gear driven supercharger, i. e., the intake manifold pressure.However, any other pressure such as the pressure of a torque nose whichmeasures engine power output or the pressure between the carburetor andthe geared supercharger may be used.

For positioning the throttle valve l2, there is provided a reversingelectric motor 50 having a field winding 5| which effects operation ofthe motor in a direction to move throttlevalve I2 toward open positionand a field winding 52 which effects operation of the motor in adirection to move throttle valve I2 toward closed position. At 53 is asuitable stop which is engaged by arm l8 to limit the opening movementof throttle valve l2. Shaft 54 of motor 50 is adapted to be 62 having aportion of larger diameter which slides in an opening ina fixed wall 63.Splined on shaft 62 is a worm gear 64 through which shaft 62 may slideaxially. Worm gear 64 meshes with the teeth of a worm wheel 65 whichforms a part of gearing 56. Movable armature 6| is biased to a positionaway from stationary armature 59 by a spring 66 positioned between ablein the casing but normally held against movement relative to the casingby a spring 45 located between the head and the other end of the casing.Spring 45 is of a stiffness such that normally rod 45 functions as asolid rod to posiftion propeller governor 49. When the one section ofrod 45 is locked against movement by energizing electromagnet 45 tobring the teeth on head 45* into engagement with the teeth 45, the othersection still can be moved by reason of the yielding of spring 45 thuspermitting adjustment of the control lever 38 even though the propellergovernor is locked in a fixed position.

Innconnection with the foregoing mechanical means operable directly bythe pilot control lever for setting the throttle valve and the propellergovernor for a desired engine load, there is provided electrical meansfor adjusting the throttle valve and for adjusting the waste gate valveto maintain automatically on the engine the load for which the controllever 38 is set. Such automatic adjustment may be under control of andresponsive to any operating condition of the engine which bears adefinite relation to the load wall. 63 and a collar on the enlargedportion of shaft 62. When winding 60 is not energized, the parts standin the positions shown in the drawing, movable armature 6! being spacedfrom stationary armature 59. When'winding 60 is en ergized, armature BIis moved axially into engagement with armature 59, shaft 62 slidingaxially-through worm gear 64, thus connecting the motor through gearing56 and clutch 58 to shaft 29. When winding 60 is deenergized, spring 66moves armature 6| away from stationary armature 59 to disconnect motor50 from shaft 29 and to bring the movable armature 6| into engagementwith a stationary friction disk 61 fixed to wall 63 toeifect promptstopping of turning movement of shaft 29. Clutch 58 comprises anelectromagnet having a stationary armature 10 fixed on shaft 51 andprovided with a Winding H and an axially movable armature l2 carried bya sleeve which is splined on shaft 29 so that it may slide axiallythereon. The sleeve which carries armature 12 is axially movable inanopening in a supporting wall 13 and is biased to a position in whicharmature 12 is separated from armature 10 by a spring 14 located betweenwall 13 and a collar on the sleeve. When winding H is energized, iteffects movement of movab'le armature 12 into driving engagement withstationary armature 10, thus connecting shaft 5! to shaft 29. WhenWinding 1| is deenergized, the clutch is opened by spring 14.

When motor 50 is operated in one direction or the other to turn shaft29, it turns arm 28 to e1,- fect movement of lever 21, the leverpivoting around its right-hand end which is held fixed by reason of itsconnection to control lever 38, and through link 26 and shaft I 6efiectsadjustment of throttle valve I 2. In this connection, it is to beunderstood that control lever 38 remains fixed in any position to whichit may be adjusted either by reason of friction or a suitable locking.arrangement.

aeveoee 5 At 15 is indicated the lever arm which is moved tov adjust thefuel mixture. It is connected by 8' rod I6 to a pilot's hand controllever 11 which is pivoted on a fixed fulcrum indicated at II. By meansof lever 11, the pilot can at any time adjust the fuel mixture.

Waste gate valve 23 is positioned by a reversing electric motor 80having a field which, when energized, operates the motor in a directionto effect closing movement of waste gate valve 23 and a field 32 which,when energized, operates the motor in a direction to effect openingmovement of waste gate valve 23. The shaft 53 of motor ll is connectedthrough a clutch brake 34, similar to clutch brake 55, and a wormgearing 44 to a shaft 01 which in turn is connected through a gearing30, an arm 39 fixed on a gearing shaft 50, and a link 9I to waste gateoperating arm 24. Brake clutch 04, being similar to brake clutch 55already described, does not require further description. Its winding isindicated at 92. A clutch 55', similar to clutch 58, is located in shaft51 between gearings 85 and 58. Its winding is indicated at 55.

Waste gate valve 23 is biased to a predetermined position by suitablebiasing means whereby when it is free to move, for example when clutch86 is disengaged, it will move to such position. In the presentinstance, it is shown as being biased to a partially closed position bya pair of opposed springs 90 operating on opposite sides of an arm 90fixed on shaft 90. However, it is to be understood that this is only byway of example as it may be biased to fully open position, or it may bewithout biasing means. If without biasing means, the clutch 95' may beomitted. With clutch 86' omitted, valve 23 will remain in whateverposition it may be adjusted to by its motor.

The circuits for field windings i and 52 of motor 50 are controlled byrelays I00 and IN, respectively, the windings of which are indicated atI02 and I03; Similarly, the circuits for field windings III and 82 ofmotor 80 are controlled by relays I04 and I05, the relay windings ofwhich are indicated at I05 and I01, respectively.

On shaft I5 is a fixed arm H0 which functions to open a limit switch IIIin circuit with relay winding I02 and to close a transfer switch II2.Switches III and H2 are biased to the position shown in the drawingwherein switch I I I is closed and switch H2 is open. They are engagedby arm I I 0 and moved to open switch I I I and close switch I I2 whenthrottle valve I2 is almost open, lacking for example a few degrees ofbeing fully open. Switch III and switch II2 are operated a few degreesprior to the time arm I3 on throttle valve I2 reaches stop 53. On shaftI5 is a second arm II3 which engages a bridging member II 4, moving itinto engagement with two contacts III and H5 and connecting the twocontacts to ground, as indicated at I". Arm II3 operates bridging member4 during the final movement of throttle valve I2 to fully open position,the operation occurring after arm II 0 has reversed the positions ofswitches III and II 2. In other words, arm II3 operates bridging memberII4 to connect contacts H5 and H5 to ground as arm I3 on throttle valveI2 moves through the final few degrees into engagement with stop 53 inwhich position throttle valve I2 is fully open.

Also, on shaft I 5 is an operating arm I I3 which stands between twonormally open circuit closers H9 and I20. Arm H8 is not fixed rigidly onshaft I5 but is frictionally connected therewith by 6 means of a yokeI2I which is held clamped around the shaft by a bolt I22 and spring I23. By adjusting the nut on the end of bolt I22, the compression ofspring I23 can be adjusted to vary the friction with which yoke I2I isclamped on shaft II. The arrangement is such that arm III moves withshaft I 0 in either direction until it closes circuit closer II! or Iafter which shaft I5 can continue to move, sliding in yoke I2I andmaintaining the circuit closer H9 or I20 (as the case may be). closed.Adjustability of arm III with respect to circuit closers H9 and I20 isprovided by making the free end of arm H5 in the form of an adjustablehead H3 having a wedgeshaped end for engaging and moving the circuitclosers. By adiusting head II0' by means of the screw and slotconnection shown the beveled sides of the wedge-shaped head may bepositioned with respect to the circuit closers to effect closing of themwhen a desired degree of movement of shaft I5 takes place.

On motor shaft 54 of motor 50 is a speed governor I24 which, when thespeed of motor 50 reaches a predetermined high value, operates to open acircuit closer I25 of a type normally biased to closed position. In thepresent instance, a known type of fly weight speed governor isillustrated, it being shown as fixed at one end on an extension of shaft54 as is indicated at I25, and as having its other movable and providedwith a collar I 21 adapted to engage the movable member I23 of circuitcloser I25. The springs of the flywheel governor are indicated at I29and the weights at I30. The arrangement illustrated is to be taken astypical of any suitable speed responsive device which, when the speed ofmotor 50 reaches a predetermined high value, efiects an opening movementof circuit closer I25 and which when the speed decreases below apredetermined value permits the circuit closer to again close.

On shaft 29 is fixed an arm I3I which opens a limit switch I32 incircuit with relay winding I03 just prior to the time arm 28 reachesstop 49.

Fixed on shaft 90 is a cam I33 (see Fig. 2) which engages with a yokeI34 on the end of an arm I35 pivoted on a fixed support I35. On arm I35but electrically insulated therefrom and from each other (for examplearm I35 may be formed from suitable insulating material) is a pair ofadjustable contacts I31 and I38 between which is located one end of acontact arm I39 also pivoted on fixed support I35. The other end of armI39 is provided with a pin I 40 which fits in a slot I H in a projectingear on a lever I42. The upper end of slot MI is defined by an adjustablestop in the form of a screw I which is threaded into the top wall ofslot HI and may be screwed up or down to vary the distance arm I39 andlever I42 may move relatively to each other before pin I40 strikes theend of stop screw I4I. One end of lever I42 is pivotally mounted onsupport I35, it being mounted around the same pivot as are levers I35and I39. The other end of lever I42 is pivotally connected to stems I43and I44 on the movable ends of flexible bellows I45 and I 45. The otherends of bellows I45 and I45 are mounted on suitable fixed supports I41and I40. Stern I 44 of bellows I45 is connected to lever I42 at a.distance from its fulcrum point on support I35 greater than that atwhich stem I43 of bellows I45 is connected. Thus, bellows I45 has alonger lever arm than does bellows I45. The length of the lever arm ofbellows I45 may be adjusted by moving the bellows relatively to the arm,a pin and slot connection I43- being indicated to per;

Bellows I45 has its interior connected by a pipe line I40 to the intakemanifold of engine I, be-

yond carburetor 5, whereby it is subjected to intake manifold pressure.The central portion of pipe line I49 is shown as being broken away inthe interest of clearness. Bellows I45 and I46 are opposed to each otherand both are subjected to the same pressure on their exterior.

Attached to lever I42 by a suitable stud I50 is the frame I50 of anelectromagnet, the armature of which is indicated at Ill and the windingat I50. Armaturel50 is pivoted on stud I50 and at its one end carries apost I50 on the free end of which is a finger I50 which extends alongthe side of the projection on lever I42 in which slot I is located. PinI40 extends entirely through slot I4I sothat its end stands under fingerI50,

the finger forming a stop for the pin against which it is'held' normallyby .a spring I50 attached to contact arm I39. Finger I50 held normallyin a fixed position by .a spring :I50 which holds finger I50 against astop 50 on arm I42. When winding I50 is energized, armature I50 is movedabout its pivot to bring its right-hand end down against the pole faceof frame I50 against the action of spring I50 thus moving finger I50upward away from pin I 40 and stop I50 At I50 is an adjustable stop forlimiting movement of lever I42 in the one direction.

Connected with the movable end of bellows I45 through the intermediaryof a spring I5I is one end of a stem I52, the other end of which ispivotally connected to an intermediate point on an arm I53. One end ofarm I53 is pivoted on a fixed support I 54. Its other end is providedwith a roller I55 which'engages a cam surface on a cam I56 fixed onshaft 32. Movement of the cam surface of cam I56 under roller I55 servesto adjust the tension of springI5I and hence the pressure setting ofbellows I45, 1. e., of the regulator. when control lever 39. is inidling position, en-

'gages the movable member of and opens a circuit closer I58 of a' typewhich is biased to closed position.

Fixed on shaft 90 is an arm I59 which in one extreme position (theposition in which waste gate valve 23 is wide open) engages and holdsopen a limit switch I59 for motor 80 and holds closed a transfer switchI59 for motor 50 and which in the other extreme position engages andholds open a second limit switch- I59 for motor 00. Switches I59 and I59are of a type biased toward closed position and switch I59 is of a typebiased toward open position.

, The control mechanism comprising bellows I45 and I46 and associatedparts are enclosed preferably in a sealed casing I59 which is connectedby a pipe line I59 to inlet conduit I I. of the compressor. Thus thepressure in casing I59 to which bellows I45 and I46 are'subjected ontheir outer sides is the ram pressure which may be On shaft 32 is an armI51 which,

. 8 which the regulator functions automatically to adjust throttle valveI2 and waste gate'valve 23 to maintain such load on the engine. Inmoving his control lever at a time when throttle valve I2 is notsubstantially fully open, the pilot manually adjusts throttle valve I2and at the same time he adjusts the setting of the regulator, i. e., thetension of spring I5I. Also, at the same time he adjusts the setting ofthe propeller governor 49. However, the arrangement is such that whenthe pilot moves his control lever, adjusting simultaneously the positionof throttle valve I2 and the setting of the regulator, the regulator isset for an intake pressure somewhat higher than that for which thecontrol lever sets the throttle valve. As a result, whenever the pilotsets the -.control lever for a desired load, he actually sets intakemanifold pressure corresponding tothe load for which the control leveris set. To this end, throttle valve'l2 is first substantially fully'opened after which waste gate valve 23 is gradually closed, thusbringing the supercharger into operation.

It is to be noted that control lever 38 is at all times directlymechanically connected to throttle valve I2 so that at any time thepilot can operate throttle valve I2 independently of the'functioning ofthe automatic control.

In the drawing, control lever 30 is shown as occupying anintermediate-position, thus setting somewhat higher than ambientpressure and by The arrangement is such that the pilot can set hiscontrol lever for a desired engine load after the propeller governor fora certain engine speed and the regulator spring I5I for a certain intakemanifold pressure. The main switch I60 located in the pilots cabin I 6|is closed, thus connecting a suitable source of .current I62 to a mainline wire I63. Circuit closer I58 is in main line wire I63 and suchcircuit closer is in closed position since control lever 38 is not inidling position. When switch I60 is closed and control lever 38 is in aposition other than engine idling position, a circuit is closed throughclutch winding II by way of line wire I63 and conductors I14, I15 andI16 to ground to effect closing of clutch 58 thus connecting shaft 51 toshaft 29. Also a circuit is closed through clutch winding 86 by way ofline wire I63 and conductors I14, I11 and I18 to ground to eiiectclosing of clutch 86 thus connecting gearing 06 to gearing 88. Contactlever I39 is midway between contacts I31 and I33 which means that thereobtains in the intake manifold a pressure corresponding to that forwhich the regulator has been set. The positions of the parts in thedrawing assume also that flight conditions are such that the intakemanifold pressure for which the regulator has been set is beingmaintained with the throttle valve I2 '9 somewhat, lifting the left-handend of lever I 42 and bringing contact arm I" into engagement withcontact I26. Since spring I66 holds pin IlII against finger III, the twolevers I62 and Ill move as a unit. This closes a circuit on relaywinding I62 which may be traced as follows: source I62, switch I66, mainline wire I 62, conductors I14, I19, limit switch III, conductor I66,relay winding I62, conductor III, contact I26, contact lever I26 andconductor I62.to ground. Relay I6! thereupon picks up, closing its twosets of forward contacts I62 and I64 and opening its set of backcontacts I66. The closing of contacts I62 closes a circuit on winding IIof motor 66 as follows: source I62, switch I 66, main conductor I62,conductors I14 and I16, relays contacts I62,

motor field winding 6i, conductor I66 and circuit closer I26 to ground.At the same time a circuit is closed through relay contacts I on clutchmagnet winding 66 which may be traced as follows: source I62, switchI66, conductor I62, conductors I14, I11 and I61, winding 66, conductorI66 and relay contacts I to ground. Thus simultaneously motor III isstarted in operation and brake clutch 66 is closed to effect turningmovement of shaft 26 to move lever 21 in a direction to lower-rod 26,thus turning the shaft I6 in a direction to move throttle valve I2toward open position, thus. effecting an increase in intake manifoldpressure. At this time, the right-hand end of lever 21 is fixed inposition forming a fulcrum about which lever 21 is turned by arm 26. Assoon as motor 66 picks up to a predetermined speed, speed governor I26comes into operation to open circuit closer I 26, thus opening thecircuit on field winding 6|. As a result, motor BII begins immediatelyto slow down. As soon as motor 66 slows down a predetermined amount,circuit closer I25 is permitted again to close, thus again enersizingfield winding II. As a result, the field winding of motor 6| is given a.plurality of short current impulses which, in effect, function tooperate motor 50 at a low speed, thus effecting a slow opening movementof throttle valve I2. If, as a result of this slow opening movement,throttle valve I2 is opened sufllciently to restore the manifoldpressure, then bellows I45 is distended to move contact arm I 39 awayfrom contact I38, thus opening the circuit and leaving the throttlevalve in its new position. If, however, as a result of the slowmovement, the throttle valve I2 has not been moved sufficiently torestore the manifold pressure, arm II Ii on shaft I6 closes circuit 10I22, conductor Ill, conductor I", transfer switch I66", contact I21,contact arm I" and conductor I82 to ground. Relay IIII thereupon picksup, closing its two sets of forward contacts I66 and I91 and opening itsset of back contacts I6I. The

closing of contacts I66 closes a circuit on winding l2-of motor 66 asfollows: source I62, main con-" ductor I62, conductors I16 and I16,relay contacts I66, conductor I66, motor field winding 62, conductorI66, and circuit closer I26 to ground. At

the same time av circuit is closed through relay contacts I61 on clutchmagnet winding 60 which may be traced as follows: source I 62, conductorI62, conductors I14, I11 and I61, winding 66, conductor I66 and relaycontacts I61 to ground. Thus, simultaneously motor 66 is started intooperation and brake clutch 66 is closed to effect turning movement ofshaft 26 to move lever 21 in a direction to lift rod 26, thus turningshaft II in a direction to move throttle valve I2 toward closedposition, thus effecting a decrease in intake manifold pressure. As soonas motor 66 picks up to a predetermined speed,v speed governor I26 comesinto operation to open and close circuit closer I26 thus opening andclosing the circuit on field winding 62 to effect operation of motor illcloser IIS, thus providing a. shunt circuit around the speed governoroperated circuit closer I25 by way of conductor I89, circuit closer II9, conductor I96 and back contacts I9I of relay I OI to ground.Accordingly, as long as circuit closer H9 is held closed, motor 50operates continuousl to adjust throttle valve I2 toward open position.This means that valve I2 is adjusted toward open position more rapidly,thus quickly restoring the desired intake manifold pressure. After armII6 has closed circuit closer II 8, shaft I6 is permitted continuedmovement due to the frictional connection between arm H8 and shaft I6,as already explained.

66 at a slow rate of speed in the manner already described. If, as a'result of this slow operation of motor 66, throttle valve I2 is closedsuiiiciently to restore the manifold pressure, then bellows I" collapsesto move contact arm I 26 away from contact I61 thus opening the circuitand leaving the throttle valve in its new position. If, however, as aresult of the slow operation, throttle valve I2 has not been movedsufficiently to restore the intake manifold pressure to the desiredvalue, arm II8 closes circuit closer I 26 to shunt out-speed governorcircuit closer I26 after the manner already explained in connection withthe operation of circuit closer N6, the circuit being to ground by wayof the back contacts I66 of relay I66. Motor then operates at a higherrate of speed to effect more rapid adjustment of throttle valve I2 afterthe manner already explained so as to promptly restore intake manifoldpressure.

In connection with the operation of throttle valve I2, when motor 66operates at its full speed in a direction either to move throttle valveI2: toward open or toward closed position, the intake manifold pressuremay overshoot," becoming either too high or too low, as the case may be.As a result of this, contact arm I29 on the regulator, when it leavesthe one contact with which it is in engagement, may move across intoengagement with the other contact, When this happens, a readjustment ofthe throttle valve I 2 in the other direction takes place. In otherwords, in case of a decrease in intake manifold pressure, the throttlevalve may be opened to an extent such that the intake manifold pressurewill be increased to a value higher than the desired pressure afterwhich the throttle valve will be readjusted slightly toward closedposition to restore the pressure to the desired value. Similarly, in thecase of an increase in intake manifold pressure, the throttle valve I2may be closed to an extent such that the intake manifold pressure willbe decreased to a value lower than the desired pressure after whichthrottle valve I2 will be readjusted slightly toward open position torestore the pressure to the desired value.

In connection with the operation of arm III on shaft I6, it will benoted that circuit closer H9 is in circuit with the back contacts I 9|of re ay I0! and that circuit closer I 26 is in circuit with the backcontacts I86 of relay. I00. The

purpose of this arrangement is to'prevent the shunting of speed governorcontrolled circuit closer I 26 when the position ofcontact arm I36 isreversed due to "overshooting of the intake manifold pressure, thusassuring that any readjustment takes place at the lower motor speed. Forexample, when regulator contact arm I38 is in engagement with contactI38 and relay winding I02 is energized calling for movement of throttlevalve I2 toward open position and arm H8 is holding circuit closer II9closed to shunt out speed governor controlled circuit closer I26, theshunt circuit to ground around circuit closer I25 is by way of relayback contacts I6I. Now when regulator contact arm I36 reverses itsposition, moving from engagement with contact I38 into engagement withcontact I31 and energizing the windin I03 of relay IM to effectreadjustment of valve I2 toward closed position, the opening of relaycontacts I6I opens the shunt circuit around speed governor operatedcircuit closer I26,

thus insuring that motor 60 operates at its low speed even thoughcircuit closer H6 is being held closed by arm II8. Thus, anyreadjustment of throttle valve I2 in either direction as a result of thepressure regulator causing the manifold pressure to overshoot takesplace at the lower motor speed.

' As pointed out already, when control lever 38 is moved at a time whenthrottle valve I2 is not substantially fully open, to set throttle valveI2 for a different engine power or load, spring I5I is adjustedsimultaneously to set the regulator for a slightly higher engine poweror load so that after the throttle valve has been set manually, afurther adjustment of the throttle valve is effected by the automaticregulator. If the movement of control lever 38 is of more than a nominalamount, shaft I6 is turned to an extent such that either circuit closerI I9 or I is closed depending on the direction of movement. This closesthe shunt circuit around speed governor operated I switch I25, whichmeans that operation of motor 60 to effect the further adjustment of thethrottle valvewill be at its higher speed. Thus with hand operation,throttle valve I2 is quickly adjusted to the desired final position.

When the regulator in functioning to maintain the intake manifoldpressure for which control lever 36 is set, has opened throttle valve I2to a position such that it is substantially fully open (but prior to thetime it is fully open and arm I3 engages stop 53), arm IIO on shaft I6functions to open limit switch III and to close transfer switch H2. Theopening of limit switch III opens the circuit of winding I02 of relayI00, thus preventing further operation of motor 50 in a direction toopen throttle valve I2; The closing of transfer switch II 2 closes acircuit on the winding I06 of relay I04 as follows: source I62, mainline conductor I63, transfer switch II 2, conductor I99, relay windingI06, conductor 200, limit switch [53% conductor 20I, c0ntact I38,contact arm I39 and conductor I82 to ground. This causes relay I04 topick up, closing its two sets of contacts 202 and 203. Closing ofcontacts 202 closes a circuit on field winding 8I of motor 60 asfollows: source I62, main line conductor I63, conductor 204, relaycontacts 202, conductor 205 and field winding 8I to ground. At the sametime, a circuit is closed through relay contacts 203 to brake clutchwinding 62 as follows: source I62, main line conductor I63, conductor204, relay I contacts 203, conductor 206, and clutch-winding ation andmotor shaft 83 is clutched to gearing 66 toefiect turning movement ofshaft 60 and arm 66 in a direction to lift link 8i and arm 24 and movewaste gate valve 23 toward closed position. As already explained, thisserves to put the supercharger into operation. waste gate valve 23 beingmoved toward closed position to an extent such that theturbosupercharger will be operated at a speed to restore the intakemanifold pressure. Turning of shaft 60 in a direction to move waste gatevalve 23 toward closed position turns cam I33 in a counter-clockwisedirection to effect movement of arm I36 downward and thus move contactI38 away from contact arm I36. Cam I33 thus functions as a follow-updevice or restoring mechanism for the regulating device to preventovershooting" and to 'give stable operation.

From the foregoing, it will be seen that when the regulator, due todecrease in intake manifold pressure calls for further operation afterthrottle valve I2 has been substantially fully opened, the control foreffecting an increase in intake manifold pressure is transferred frommotor to motor 80.

The initial turning movement of shaft moves arm I 59 away from themovable elements of limit switch I56 and transfer switch I56, permittingthe limit switch to close and the transfer switch to open.

If the intake manifold pressure again decreases, contact arm I36 will bebrought into engagement with contact I36 again closing the circuit onrelay winding I06 of relay I04 to efl'ect a further movement of wastegate valve 23 toward closed position in the manner already described.Now, should the intake manifold pressure increase, contact arm i39 willbe moved into engagement with contact I31 closing a circuit on relaywinding I01 of relay I05 which may be traced as follows: source I62,main line conductor I63, relay winding I01, conductor 201, limit switchI56. contact I31, contact arm I36, and conductor "2 to ground. Thiscauses relay I06 to pick up, closing its two sets of contacts 208 and209. Closing of contacts 206 closes a circuit on field winding 62 ofmotor 80, which may be traced as follows: source I62, main lineconductor I63, relay contacts 208, and field winding 82 to ground. Atthe same time, the closing of the circuit across relay contacts 209closes a circuit on clutch winding 92 which may be traced as follows:source I62, main line conductor I63, relay contacts 206, conductor 206,and clutch winding 62 to ground. As a result, brake clutch 64 is closedand motor 60 operates in a direction to move waste gate valve 23 towardopen position, thus eflectinga decrease in pressure in the intakemanifold. During its operation, shaft 66 turns cam disk I33 in aclockwise direction thus lifting the right-hand end of lever I36 to movecontact I31 away from contact arm I39. If the regulator callscontinuously for increase in manifold pressure, waste gate valve 23 iscontinuously moved toward closed position until it reaches a maximum atwhich time arm i56 on shaft opens limit switch I66,

thus preventing further operation of motor 66 in a direction to effectclosing movement of waste gate valve 23. On the other hand, if while thesupercharger is in operation, the intake manifold pressure continues toincrease, motor 66 will be operated by the regulator to effect openingmovement of waste gate valve 23 until it is fully open whereupon arm I56on shaft 60 engages and 13 opens limit switch I53 and closes transferswitch I53". When transfer switch I53 is closed, a circuit is closed onwinding I03 of relay III which may be traced as follows: source I42,main line conductor I33, conductors I14, I15, I32, relay winding I03,conductor I33, limit switch I32, conductor I34, conductor I35, transferswitch I53", contact I31, contact arm I33 and conductor I32 to ground.This causes relay IM to close. thus effecting operation ofthrottle valveI2 toward closed position to effect a decrease in the intake manifoldpressure. Thus, it will be seen that when the regulator, due to increasein intake manifold pressure, calls for further operation after wastegate valve 23 is fully open, the control for eiIecting a decrease inintake manifold pressure is transferred from motor 03 back to motor 50.

Considering the foregoing, it will be seen that when the control isoperating on throttle valve I2, opening of limit switch III opens thecircuit 14 charger so that its speed is proportional to the superchargerspeed. For example, it may be driven from the supercharger oil pumpshaft. The output of generator 2 I0 is connected by conductors 2| I to aload circuit through a tuned circuit comprising an inductance 2 I2 and acapacitor 2 I3 serially arranged with respect to one another. Thepurpose of this tuned circuit is to make the overspeed control moresensitive when the supercharger is operating near its maximum speed byarranging the values of the inductance 2 I2 and capacitor 2I3 so thatthey provide a resonant circuit at the frequency of generator 2I0 whenoperating atthe-maximum speed of the supercharger. With thisarrangement, at maximum speed the capacitance and inductance neutralizeone another and output current from generator through control contact I33 andrelay winding I02, the closing of which circuit by contact arm I33eifects operation of motor 50 in a direction to open throttle valve I 2,and the closing of transfer switch II2 closes the circuit betweencontrol contact I33 and relay winding I04. the closing of which circuitby control arm I33 effects operation of motor 30 in a direction to closewaste gate valve 23; and conversely, when the control is operating onwaste gate valve 23, the opening of limit switch I53 opens the circuitbetween control contact I31 and relay winding I01, the closing of whichcircuit by control arm I33 effects operation of motor 00 in a directionto open waste gate valve 23, and the closing of transfer switch I53closes the circuit between control c ontact I31 and relay winding I03,the closing of which by control arm I33 effects operation of motor 50 ina direction to close throttle valve I2.

The circuit of relay winding I02 of relay I00,

the relay which closes the circuit on field winding SI of motor 50 tooperate it in a direction to open throttle valve I2, is connected alwaysto control contact I30 except when limit switch III is open; andsimilarly relay winding I01 of relay I05, which relay closes the circuiton field winding 32 of motor 00 to operate it in a direction to openwaste gate valve I2, is connected always to control contact I31 exceptwhen limit switch I53 is open. -Thus, whenever limit switch III is inclosed position, throttle valve I2 can be operated toward open positionto increase the manifold pressure by the control arm I33 engagingcontact I38 and whenever limit switch I53 is in closed position, wastegate valve 23 can be operated toward open position to decrease themanifold pressure by control arm I33 engaging contact I31.

In connection with the supercharger and the regulating mechanism,thereis provided means to prevent the regulator effecting operation of thesupercharger at a speed above a predetermined high value. In otherwords, there is provided a maximum speed-governor for the supercharger.To this end, there is provided a means which, when the speed of thesupercharger reaches 'a predetermined high value, operates automaticallyto take the control away from bellows I 45 and I48 and substitutetherefor a means responsive to supercharger speed thereby placing wastegate valve 23 under control of such speed responsive means. In thepresent instance, this speed responsiv'e means is shown as comprising analternating current generator 2 I0 driven by the super- 2I0 is limitedonly by the resistance of the circuit. The output of generator2I0,'which passes through the resonant circuit just described, isimpressed across the one set of terminals of a full wave rectifier 2I4.The other set of terminals of rectifier 2I4 is connected to the winding2I5 ofa suitable torque motor 2I3 so that a direct current is impressedacross winding 2". Torque motor 2I3 has an armature 2I1 which isconnected by means of a shaft 2I3 to a cam 2Il. Armature 2 I1 and cam2I3 are biased in a direction such that cam 2I3 engages a stop 220 bymeans of a spring Hi. When a current of sufiicient magnitude energizeswinding 2I5, arma-' ture 2" of torque motor 2I8 is rotated in aclockwise direction against the tension of spring Hi to bring cam 2I3into engagement with -a projection 222 on contact arm I33 whereupontorque motor 2I6 takes control of the contact arm' I33 away from bellowsI45 and I and spring I5I. The pin and slot connection comprising pin I40and slot I4I, respectively, provides a mechanical take-over whichpermits motor 2I3 to move contact arm I33 independently of lever I42 andbellows I and I46.

To enable the pilot to adjust the maximum speed of the speed regulatoror governor, inductance 2I2 may be provided with one or more taps bymeans of which its value may be ad- Justed. In the present instance, twotaps 223 and 224 are shown either of which may be connected into circuitby a pilot's hand switch 225. Tap 223 may represent the rated or normalsafe maximum speed for the supercharger while tap 224 may represent acertain percentage over speed, it being intended for use primarily incase of emergency of a character such that the pilot finds it desirableto over speed the supercharger for a short time to increase his enginepower.

Stop I serves to limit the turning movement of lever I42 in a clockwisedirection as viewed in Fig. 1. The stop is adjusted to a position suchthat it limits upward movement of the left-hand end of lever I42 to thatposition which still will permit operation of contact I33 and arm I33when cam I33. and arm I35 are in their extreme counterclockwise or downpositions but will not permit of its movement beyond such point.

The maximum speed governor functions to limit the maximum speed to whichthe supercharger may be brought by the regulator in its effort tomaintain the intake manifold pressure for which the control lever "maybe set.

The function of the finger I50 is to permit of an increase in the intakemanifold pressure beyond that for which the regulator is set nor- .15desirable under certain emergency conditions. To this end, winding ll8is connected in circuit by a conductor 228 and a pilots hand switch 221to source I82. When switch 221 is closed, armature I80 is actuated tobring its right-hand end into engagement with the adjacent pole face,thus lifting fiinger "8 away from pin I" to a position where it is abovethe lower end of adjustable stop screw HI. This frees lever I38 formovement'and spring I will tend to move it into engagement with the endof stop screw Ill. As a result, the end of lever I33 engages contactI38, whereupon the control mechanism operates to effect an increase inmanifold pressure, the increase being that defined by theadjustment ofstop screw Ill. When the desired higher pressure is reached adjustmentscrew I and pin I engage to control the pressure at this value. Ineffect, the arrangement operates to permit of the adjustment of thelinkage or connections between the bellows and I48 and the contact "armI33 thus changing the intake manifold pressure represented by a givenposition of the control lever 38. Ordinarily, this adjustment will beused only when the pilot, after having brought his control lever 38 tonormal maximum power position, finds thatto meet an emergency he needs,atleast temporarily, a further increase in power. This he can obtainquickly by closing switch 221 to effect the operation already described.Stop screw HI may be set to permit the pilot to obtain an intakemanifold pressure a predetermined amount higher than the maximum whichcan be obtained normally by movement of control lever 38.

To advantage, pilots hand switches 225 and 221 may be connected togetherfor simultaneous, operation as shown, although they may be arranged forseparate operation. When both are closed, the regulator is set for ahigher maximum intake manifold pressure and the maximum speed governoris set for a higher maximum supercharger speed. Thus, if needed, asupercharger speed higher than that normally permitted may be obtainedin order to obtain the higher manifold pressure.

In the drawing, control lever 38 is shown as being positioned for anintermediate load on engine i; throttle valve i2 is shown as being in apartly. open position, and waste gate valve 23 is shown as being wideopen. This may represent the positionsof the respective valves in orderto maintain the desired load on the engine, 1. e., the desired intakemanifold pressure in the present instance, at a certain altitude. Foroperation at a lower altitude, throttle valve l2 would be adjusted bythe automatic regulator toward closed position. For operation at ahigher altitude, throttle valve l2 would be adjusted by the automaticregulator toward open position. And, when substantially fully open,lacking only a few degrees, as already explained, waste gate valve 23will be gradually closed by the automatic regulator. Thus, for anyparticular setting of control lever 38, throttle valve l2 may bepartially open and waste gate valve 23 fully open; substantially fullyopen and waste gate valve 21 fully open; or substantially fully open andwaste gate valve 23 closed to a lesser or greater degree depending onthe altitude. This is because the amount of supercharging requiredvaries directly with the altitude.

At any time, the pilot can decrease or increase the load on the engineby adjusting his control lever 38. If 'a' decrease in load is desired,control lever 38 is moved in clockwise direction, as

then waste gate valve 23 will be adjusted to bring dis-Moos shown in thedrawing to simultaneously move throttle valve i2 toward closed positionand adjust the tension of regulator spring I8 I. Ifat this time wastegate valve 23 is fully open, the automatic regulation being eflected bymeans of throttle'valve l2, the control lever 38 first moves the valve I2 to a new position after which the regulator adjusts the throttle valvefor the new pressure for which regulator spring MI is set. is alreadyexplained, a movement of control lever 38 sets the regulator for anintake manifold pressure slightly higher than that to which the throttlevalve I2 is adjusted. If at the time control lever 38 is moved, throttlelever i2 is substantially fully open and waste gate valve 28 ispartially closed,

the intake manifold pressure down to the desired value. Under theseconditions, throttle valve 12 will have been moved somewhat towardclosed position and will remain in such position until there occurs thefirst demand by the regulator for an increase in intake manifoldpressure at which time the throttle valve will be moved toward openposition since when throttle valve i2 was moved toward closed position,transfer switch ill was permitted to close, thus closing the circuitbetween controlcontact I38 and relay winding I02. This is not material,however, since the initial degreesof movement of a valve of the type ofa throttle valve from open position toward closed position has littleregulating effect on the flow past it.

Similarly, the pilot can increase the load on the engine at any time bymoving control lever 38 ,in an anti-clockwise direction, as shown in theengine power, throttle valve i2 is in its substantially fully openposition and the regulator is operating on waste gate valve 23, thenspring i5! will be reset for a higher intake manifold pressure and theregulator will effect operation of motor to move waste gate valve 23toward closed position by the amount necessary to ive the increasedmanifold pressure corresponding to the new regulator setting. At thesame time throttle operating motor 50 will be operated in a direction tomove throttle valve i2 toward closed position, thus preventing themovement of control lever 38 from jamming the mechanical connectionbetween the control lever and throttle valve l2. This latter result iseffected as follows: When .control lever 38 is moved to readjust thesetting of regulator spring i5i at a time when throttle valve I2 is inits substantially fully open position, the first movement of the leverbrings arm M3 on shaft l6 into engagement with bridging contact III toconnect contacts H5 and H6 directly to ground and a further movementbrings arm l3 on the throttle valve into contact with stop 53.Connecting contact H5 to ground closes a circuit on field winding 52 ofmotor 50 to effect operation of the motor in a direction to movethrottle valve l2 toward closed position; and connecting contact 6 toground operates to connect a shunt circuit around speed governoroperated circuit closer I25 so .thatmotor 50 operates at its higher rateof speed. When contact I I5 is grounded by bringing member H4, a circuitis closed through relay move throttle valve II toward closed position inthe manner already explained. At the same time the grounding of contactIII connects a shunt circuit to ground around speed governor operatedcircuit closer III by way of conductor III, conductor III, and contactIII to ground at I". Thus by utilizing the final few degrees of movementof throttle valve II toward open position to effect operation of motorII at its higher speed in a direction to move valve II toward closedposition, the pilot, irrespective of the positions of throttle valve IIand waste gate valve II, can always safely move his control lever II toset the regulator for a higher intake manifold pressure and a higherload on the engine.

This arrangement whereby when the control lever is operated to adjustthe regulator for a higher intake manifold pressure at a time when theregulator is working on the waste gate valve, there is effected, so tospeak, an operation of the throttle valve in a direction opposite tothat in which the control lever tends to move it, is regarded as animportant feature of the invention. By such arrangement, the controllever is always directly mechanically connected to the throttle valve.This is advantageous since by reason of such arrangement whereby thecontrol lever II isdirectly mechanically connected to the throttle valveII and always remains so connected, the pilot can directly mechanicallyoperate the throttle valve quite independently of motor III or theautomatic regulator. This is important since if at any time theregulator fails to function,

- the pilot is always in a position to take over the control manually,and by such manual control he always can operate the throttle valvethroughout its entire range. In this connection, it is pointed out thatthe engine may be controlled manually by throttle II, irrespective ofthe position of waste gate valve II. This represents, of course, whatmay be termed emergency operating conditions and is not the intendednormal functioning of the apparatus.

When control lever II is in idling position, circuit closer III is heldopen by. arm I51 on shaft II whereby the automatic regulator isdisconnected from the circuit. Also, the automatic regulator may bedisconnected from the circuit by opening switch III which is located inthe pilot's cockpit.

When taxying and when landing, it is desirable to have the enginethrottle valve on manual control alone and not on automatic control.Also on take off, it is preferable to have the engine throttle valve onmanual control alone although on take of! there may be times when somesupercharging is required to give the needed power. To meet theseconditions, there is provided means whereby the waste gate valve motor80 only may be connected to the automatic regulator, throttle motor Ibeing disconnected therefrom. Such means may be operated manually.Preferably, however, such means is placed under control of the landinggear in a manner such that when the landing gear is down only waste gatevalve motor II is connected to the automatic regulator while when thelanding gear is up, both motors II and II are connected to the automaticregulator. Or otherwise stated, assuming both motors are connected tothe automatic regulator and the landing gear is up for normal flightconditions, then when the landing gear is lowered to make a landing, thethrottle operating motor II is automatically disconnected from theautomatic regulator.

To accomplish the foregoing, there is provided a switch III in the powercircuit to the relay contacts III and III which control the circuits ofmotor field windings II. and II of throttle motor II- By opening switchIII, the automatic regulator is disconnected from the throttle valve II,while it remains connected to waste gate valve II.

If switch III is manually controlled. then on take oi! the pilot mayclose main switch III to put power on the regulating system and openswitch III to disconnect motor II from the power circuit. Then. if whencontrol lever II is moved to take oil position, in which positionthrottle valve II is substantially fully open, the desired intakemanifold pressure called for by the setting of lever II does not obtain,the regulator will operate to effect closing movement of waste gatevalve II to the extent needed to operate the supercharger at a speedwhich will give the desired intake manifold pressure- In thisconnection, it is to be noted that when control lever II is moved totake 08 position, arm III on shaft II closes transfer switch III toconnect the regulator to motor II.

such that when the landing gear is down, the

switch is held open while when the landing gear is retracted, theswitchis closed. In the'drawing III is a spring which biases switch 228 toclosed position and III is a rod connected with the landing gearoperating lever and operated by the landing gear operating lever to openthe switch when the landing gear is down. Referring to Fig. 3. rod IIIis provided with a cam or projection III which slides under the switchstem to open the switch when the landing gear lever III is moved tolower the landing gear.

After take oil, the pilot may open switch I60 and operate the enginemanually by means of throttle valve II, the automatic control beingdisconnected until such time as he desires to place the engine underautomatic control.

As already pointed out, cam III, in adjustin arm III and thus thecontacts I31 and I38, functions as a follow-up device to provide acertain width of regulation or pressure droop between light load andfull load on the turbosupercharger to give stability to the regulatorand prevent hunting when controlling the turbosupercharger, This meansthat for any given setting of the regulator the pressure maintained atfull load on the turbosupercharger is a certain amount lower than atlight load on the turbosupercharger. The purpose in providing forbellows III a lever arm longer than that for bellows I, in other words,having the bellows offset relatively to each other, is to compensate inpart at least for such pressure drop so as to.

I42 is proportional to the bellows area and the distance 01' itsconnection from the pivot point.

lows I 46 acts to readjust the regulator serves to.

counterbalance to a predetermined extent the action of cam I33. As aresult, the actual pressure droop or width of regulation of theregulator is decreased over what it would be were bellows I45 and I46not offset relatively to each other.

Features of the regulator disclosed are not claimed herein specificallyas they form subject matter of an application of Martin Levine, SerialNo. 518,532, now Patent 2,376,144, filed on even date herewith andassigned to the same assignee as the present application.

When control lever 38 is moved, lever 21 pivots on the end of arm 28 toraise and lower rod 26 and thus adjust throttle valve I2; and when motor50 turns shaft 29, lever 21 pivots around the lower end of rod 39 toraise and lower rod 26 to adjust the throttle valve. These twoadjustments are additive, the position of the throttle valve at any timebeing the sum of the two movements. Spring 49 biases arm 28 to aposition in engagement with stop 49. When lever arm 28 is in engagementwith stop 49, the pilot has full control of the'throttie valve.

Whenever solenoid winding II is deenergized by the opening of switch I60or circuit closer I58, or by electric power failure, clutch 58 isdisengaged and lever arm 28 moves instantly into engagement with stop49, bringing throttle valve I2 to a position corresponding to theposition occupied by control lever 38. At the same time, if a clutch 86ais provided, it will be disengaged, permitting waste gate valve 23 to bemoved to the position to which it is biased by springs 90. If a clutch86 is not provided, then waste gate valve 23 will remain in the positionto which it has been adjusted by its motor 80.

Intake manifold pressure is a measure of the power output of the engine.By setting control lever 38 for a desired engine power output, themaintaining of the corresponding intake manifold pressure constant(assuming constant engine speed), maintains on the engine the poweroutput for which the control lever is set. For every intake manifoldpressure, 1. e., engine power output, there is a definite engine speedwhich gives best engine efliciency, and cam slot 42 is shaped to set thepropeller governor for such engine speed. Under certain conditions,however, for example, to obtain better efficiency on long flights atcruising speeds, it may be desirable to adjust the intake manifoldpressure relatively to the engine speed. In other words, to change therelation between power output and engine speed. To accomplish this, thepilot may, after setting his control lever for a certain power outputand engine speed, close a push button switch 234 thus closing a circuiton the winding 235 of a normally open relay of the self locking-in typeas follows: main line conductor I63, conductors 236 and 231, push buttonswitch 234, conductor 238, relay winding 235 and a normally closed cir-20 cuit closer 239 to ground. This causes the relay to pick up, bridgingits two sets of contacts 240 and MI. Bridging of contacts 249 closes acircuit on solenoid winding 45 and bridging of contacts 24I closing aholding circuit for relay winding 235 in shunt to push button 234. Thusthe relay is locked in, maintaining solenoid winding 45 energized. Whensolenoid winding45 is energized, its plunger brings locking head 45 inengagement with the teeth 45*- on rod 45 to lock the rod in a fixedposition. Now by moving control lever 38 in an anti-clockwise direction,the regulator may be set for a higher manifold pressure without changingthe setting of the pro-' peller governor, spring 45 yielding to permitThus a manifold pressure a desired amount higher than that which wouldnormally be used at the given engine speed may be'obtained. When anincrease in power is called for, the pilot, by pushing forward oncontrol lever 38 can bring collar 242 into engagement with the movableelement of circuit closer 239 to open the holding circuit on relaywinding 235, to deenergize the relay and permit it to open. This opensthe circuit on solenoid winding 45 permitting head 45 to drop fromengagement with teeth 45, thus releasing rod 45 and permitting spring 45to effect an adjustment of the propeller governor.

In Fig. 1, the arrangement is such that after the propeller governor islocked, the manifold pressure can be only increased relatively to thepropeller speed. However, the arrangement may be such that it may beeither increased or decreased if desired. An arrangement foraccomplishing this is shown in Fig. 4 wherein head 243, corresponding tohead in Fig. 1, is arranged between a pair of springs 244 and 245whereby after the propeller governor is locked for a certain speed, thecontrol lever may be moved in a direction either to increase or decreasethe manifold pressure.

In Fig. 5-is shown a modified arrangement for enabling the pilot toadjust the maximum speed of the speed regulator or governor driven fromthe turbosupercharger, it differing primarily from the arrangement shownin Fig. 1 in that the capacitance of the tuned circuit is varied ratherthan the inductance. In Fig. 5, the same reference characters with aprime added have been used to designate corresponding parts. Thealternating current generator 2I0' is connected by a conductor 250 toone input terminal of rectifier 2I4'. The other input terminal isconnected by a conductor 25I to two capacitors 252 and 253 arranged inparallel. This terminal is connected also by a conductor 254 to acapacitor 255. Adjacent capacitor 255 is another capacitor 256 which isnot in this instance connected in the circuit. In the conductor 254 is amanual switch 25'! adapted to be operated by the pilot and a secondswitch 258 which is opened automatically by pilots control lever 38 whenit reaches a position to a predetermined intake.

manifold pressure power. In circuit with the four capacitors is aninductance 2 I2 and an adjustable resistance 259, the two beingconnected in series to the other terminal of generator 2I9 by aconductor 260. With the connections shown, it will be seen that thethree capacitors 252, 253 and 255 are connected into the circuit inparallel and that capacitor 255 is in circuit with the manual controlswitch 251 and the control lever operated switch 258. The capacitors areof such value that with the three capacitors concanoes 2inectedincircuitasahowmthecircuitwiilbe tuned tor the desired normalmaximum turbosupercharger speed. To increase this maximum, the pilot mayopen the hand switch "I thus removing the onecapacitor from the circuit.Also. this capacitor is removed automatically irom the circuit by, theopening oi switch ill when the pilot's lever is movedto the positionrepresenting a certain predetermined maximum maniiold intake pressure.By varying the connections to the several capacitors. the normal maximumspeed and what maybe I maximum speed may be adjusted with respect toeach other. By arranging the connections so that more capacitance isremoved from the circuit when either switch I" or switch Ill is opened,a greater increase in speed can be provided for. In use of the device,it. may be decided in advance what maximum speeds are desirable and thecapacitors adjusted accordingly. By way of example, it may be desirablethat the normal maximum speed of the turbosupercharger be 20,000 R. P.M. and that the emergency maximum speed be 24,000 R. P. M. 26,000 R. P.M. or more. By correctly tuning thecircuit and adtermed the emergencyjusting the capacitor connections. the desired speed values can beobtained. The adjustable resistance 250 may be utilized to enable thepilot to adjust the maximum turbosupercharger speed within certain smalllimits. For example, the change in speed obtainable by adjustingresistance 250 may be of the order of 500 R. P. M. with thisarrangement. the resistance arm may be set midway of the resistance.Then, assuming the ilgure given, the pilot may by means of resistance25! at any time increase or decrease the maximum obtainable speed of theturbosupercharger by 250 R. P. M. It will be understood that the figuresgiven are only by way or example. The arrangement may be such as topermit the pilot to adjust the speed by means oi resistance 2" by theamount deemed desirable for any particular installation. It will beunderstood that the arrangementshown in Fig, 5, may be used inconjunction with the pilot's hand switch 221 which is utilized toincrease the maximum intake manifold pressure.

In accordance with the invention, it will be seen that there is employedonly a single control lever for the engine throttle valve, theturbosupercharger waste gate valve and the propeller governor, thesingle control lever when adjusted eiiecting the correct adjustment ofall three elements to give the mosteiilcient engine operation. Thissingle control lever replaces the three separate control levers usedwhen the engine throttle valve, the turbosupercharger waste gate valveand the propeller governor are adjustedseparately and independently. Bythe invention, the pilot, instead of having to adjust independentlythree separate control levers, the adjustments being made by the use ofseparate suitable instruments and charts to properly coordinate theseveral settings, has simply to set his control lever for the enginepower desired, the adjustments of the several elements being theneilected automatically. Thus, the burdens of the pilot are reducedmaterially and more eiilcient engine operation is assured.

The construction and arrangement for carrying out the inventiondisclosed and claimed herein has substantial advantage in that it isrelatively simple in structure and reliable in operation, and, asalready emphasized, provides an arrangement wherein the pilot's controllever is 22 mechanicall connected always to the engine throttle valve sothat at direct manual control over the engine throttle In accordancewith the provisions of the patent statutes. we have described theprinciple of operation of our invention, ratus which we now consider torepresent the best embodiment thereof, but we desire to have itunderstood that the apparatus shown is only illustrative and theinvention may be carried out by other means.

what we claim as new and desire to secure b Letters Patent oi the UnitedStates. is: 4 v

1. In combination, an engine, regulating means for-the engine, a controllever connected to the regulating means for positioning it, a controldevice responsive to a control force which is a measure of an operatingcondition 0! the engine connected to the regulating means forpositioning it in response to changes in 'the value of such force, meansfor adjusting the setting oi said control device, and means connectingsaid adjusting means to said control lever which sets the control devicefor a value of said control i'orce different from that for which it setsthe control device.

2. In combination, an engine, valve means for regulating the engine, acontrol lever connected to said valve means for positioning it, acontrol device responsive to a control force which is a measure of thepower output of the engine connected to said valve means for positioningit in response to changes in the value of said control force, adjustablemeans for changing the setting of said control device, and meansconnecting said adjustable means to said control lever which sets thecontrol device for a control force greater than that for which the valvemeans is positioned by the control lever.

3. In combination, an engine, valve means which is adjusted to vary thepower output of the engine, a control lever for positioning said valvemeans manually, an electric motor, means connecting the electric motortosaid valve means for positioning said valve means, an automatic controldevice responsive to a control force which is a measure of engine poweroutput for eilecting operation of said motor, means connected with saidcontrol lever for adjusting the setting of said control devicesimultaneously with the manual adjusting 01 said valve means, meansbiasing said motor connecting means toward a position wherein the valvemeans is closed, and means for disconnecting the motor from said motorconnecting means.

4. In combination, an engine, valve means which is adjusted to vary thepower output .of the engine, a control lever for positioning said valvemeans manually, an electric motor for positioning said valve means,an'automatic control device responsive to a control force which is ameasure of engine power output, a floating lever through which saidmanual control lever and said motor are connected to said engine valvemeans for adjusting it, means for adjusting the setting of saidautomatic control device which is connected to and operated by saidcontrol lever,

means biasing the floating lever toward a position wherein the valvemeans is closed, and

means for disconnecting the motor from said floating lever.

5. In combination, an engine, a first regulating means which is adjustedto vary the power output of the engine, a second regulating means alltimes the pilot has,

together with the cplengine, an electric motor for each regulating meansfor positioning it, an automatic control device responsive to a forcewhich is a measure of engine power output, means ior adjusting thesetting 01' said automatic control device, means operated byv the motorof the first regulating means for connecting the control device to themotor for the second regulating means, and means operated by the motorfor the second re ulating means for connecting the control device to themotor for the first regulating means.

6. In combination, an aircraft engine, a regulating means for theengine, a, supercharger for the engine, a regulating means for thesupercharger, an electric motor for each regulating means, an automaticcontrol device responsive to a to ce which is a measure of engine poweroutput, cans for adjusting the setting of said automatic control device,means operated when the regulating means for the engine reaches apredetermined position through which the electric motor for thesupercharger regulating means is connected to said automatic controldevice, and means operated when the regulating means for thesupercharger reaches a predetermined P tion through which the electricmotor for the engine regulating means is. connected to said automaticcontrol device.

7. In combination, an engine, a first valve means which is adjusted tovary the power output of the engine, a second valve means which isadjusted to vary the power output of the engine, a motor for each'valvemeans, an automatic control device responsive to a force which is ameasure of engine power output, means for adjusting the setting of saidautomatic control device, and means operated by said motors forconnecting said control device to either one or the other of saidmotors.

8. In combination, an engine, a first valve means which is adjusted tovary the power output of the engine, a second valve means which isadjusted to vary the power output of the engine, a motor for each valvemeans, manual means for positioning at least one of said valve means, anautomatic control device responsive to a force which is a measure ofengine power output, means actuated by said manual means for adjustingthe setting of said automatic control device, and means connecting saidcontrol device to said motors for effecting operation of said two valvemeans in sequence.

9. In combination, an engine, a first valve means for regulating thepower output oftheengine, a manual control member connected to saidfirst valve means for positioning it, a second valve means forregulating the power output of the engine, an automatic control deviceresponsive to a force which is a measure of engine power output, meansconnecting the automatic control device to said first and second valvemeans to eflect their operation in sequence, means connecting theautomatic control device to said manual controlmember for adjusting thesetting 01 the automatic control device, and means whereby when saidmanual control member is moved to change the setting oi! said automaticcontrol device at a time when said first valve means is at approximatelyits extreme position in one direction, there is efiected operation 01'it in .the other direction to thereby permit of continued movement ofthe manual control member.

10. In combination, an engine, a throttle valve for regulatingthe poweroutput of the engine, a manual control lever connected permanently tothe throttle valve for positioning it, a supercharger for the engine,means for regulating the supercharger, an automatic control deviceresponsive to a iorce which is a measure of engine power output, meansconnecting said automatic control device to said throttle valve and tosaid supercharger regulating means to eflect their operation insequence, said supercharger regulating means being operated after saidthrottle valve is at least substantially fully open, means connectingthe automatic control device to said manual control lever wherebymovement of the manual control lever serves to set the automatic controldevice, and means whereby movement of said control lever to eflect finalcomplete opening of the throttle valve eflects movement of the throttlevalve toward closed position whereby the control lever may be moved toset the automatic control device when the throttle valve reaches the endof its opening movement.

11. In combination, an engine, a first valve means for regulating itspower output, a floating lever connected to the first valve means, amanual control member connected to the floating lever for adjusting saidfirst valve means, a second valve means for regulating the power outputof the engine, an automatic control device responsive to a force whichis a measure of engine power output, means connecting the automaticcontrol device to said floating lever and to said second valve means foroperating them in sequence, means connecting the automatic controldevice to said manual control member for adjusting the setting or theautomatic control device, and means whereby continued movement of saidmanual control member to adjust the setting of said automatic controldevice may be efiected after said first named valve means reaches anextreme regulating position.

12. In combination, an engine, a first valve means for regulating itspower output, a floating lever connected to the first valve means, amanual control member connected to the floating lever for adjusting saidfirst valve means, a second valve means for regulating the power outputof the engine, an automatic control device responsive to a force whichis a measure of engine power output, means connecting ,the automaticcontrol device to said floating lever and to saidsecond valve means foroperating them in sequence, means connecting the automatic controldevice to said manual control member for adjusting the setting or theautomatic control device, and means whereby continued movement of saidmanual control member to adjust the setting of said automatic controldevice after said first valve means has reached an extreme positiontends to move said first valve means in a direction away from suchextreme position.

13. In combination, an engine, a throttle valve for regulating the poweroutput, a floating lever connected to the throttle valve, a manualcontrol member connected to the floating lever for adjusting thethrottle valve, an electric motor connected to the floating lever foradjusting the throttle valve, a supercharger for the engine, regulatingmeans for the supercharger, an electric motor for adjusting thesupercharger regulating means, an automatic control device responsive toa force which is a measure of engine power output, means connecting theautomatic control device to said electric motors to efiect adjustmentsof said throttle valve and said supercharger transferring connectionsmember to adjust the setting of said automatic control device after saidthrottle valve has reached an extreme open position effects operation01' said first named electric motor in a direction tending to close thethrottle valve.

14. In combination, an engine, a throttle valve for regulating its poweroutput, a floating lever connected to the throttle valve. a manualcontrol member connected to the floating lever for adjusting thethrottle valve, an electric motor connected to the floating lever foradjusting the throttle valve, a turbosupercharger for the engine,regulating means for the turbosupercharger, an automatic control deviceresponsive to a force which is a measure of engine power output, meansconnecting said automatic control device to said electric motor and tosaid turbosupercharger regulating means to eilect adjustment oi thethrottle valve and turbosupercharger regulating means in sequence, meansconnecting said automatic control device to said manual control memherfor adjusting the setting of the automatic control device, and meanswhereby continued movement of said manual control member to adjust thesetting of said automatic control device after said throttle valve hasreached an extreme open position eflects. operation of said electricmotor in a direction tending to close the throttle valve.

15. In combination, an engine, a throttle valve for regulating its poweroutput, a floating lever connected to the throttle valve, a manualcontrol member connected to the floating lever for adjusting thethrottle valve, an electric motor connected to the floating lever foradjusting the throttle valve, a turbosupercharger for the engine,regulating means for the turbosupercharger, an automatic control deviceresponsive to a force which is a measure 01' engine power output, meansconnecting said automatic control device to said electric motor, meansincluding a follow-up mechanism connecting said automatic control deviceto said turbosupercharger regulating means, means connecting saidautomatic control device to said manual control member for adjusting thesetting of the automatic control device, and means controlled by thepositions of said throttle valve and said turbosupercharger regulatingmeans for of the automatic control from the throttle valve to theturbosupercharger regulating means.

16. In combination, an engine, a throttle valve for the engine, anelectric motor for positioning the throttle valve, a turbosuperchargerfor the engine, a regulating valve for the turbosupercharger, anelectric motor for positioning said regulating valve, an automaticcontrol device responsive to a force which is a measure of engine poweroutput, and means including transfer switches actuated by said motorsfor eiIecting connection of said automatic control device to therespective motors for actuating said throttle valve and said regulatingvalve in sequence.

17. In combination, an engine, a plurality of regulating means for theengine, an electric motor for each regulating means for positioning it,an automatic control device responsive to a force which is a measure ofengine power output, and means for electrically connecting said controldevice to said motors in sequence to eiiect sequential operation 01'said regulating means.

18. In combination, an engine, a plurality of regulating means for theengine, an electric motor for each regulating means ior positioning it,an automatic control device, and electric circuits including transferswitches controlled in accordance with the positions oi said regulatingmeans, for connecting said automatic control de-- vice to said electricmotors in sequence.

19. In combination, an aircrait engine, a valve regulating admission offuel to the engine, a supercharger, a regulating valve ior thesupercharger, a reversing electric motor for positioning each regulatingvalve, an automatic control device responsive to a force which is ameasure of engine power output, and electric circuits including a limitswitch and a transfer switch for each motor for connecting the controldevice to the regulating valves sequentially.

20. In combination, an engine, valve means, a motor which positions thevalve means to vary the power output of the engine, an automatic controldevice responsive to a force which is a measure of engine power output,means connecting the automatic control device to said motor including aspeed governor operated by the motor for rendering said connecting meansineffective when the motor speed reaches a predetermined value, andmeans controlled by movement of said valve means for renderingineilective said speed governor.

21. In combination, an engine, valve means, an electric motor whichpositions the valve means to vary the power output of the engine,control contact means actuated by a force which is a measure of enginepower output, electric circuits connecting the control contact means tosaid motor, a device responsive to the speed of said electric motor forrendering said electric circuits ineifective when the motor speedreaches a predetermined value, and means actuated by movement of saidvalve means for rendering said speed responsive device inefl'ective.

22. In combination, an engine, valve means, an electric motor whichpositions the valve means to vary the power output of the engine,control contact means actuated by a force which is a measure of enginepower output, electric circuits connecting the control contact means tosaid motor, a device responsive to the speed or said electric motor foropening said electric circuits when the motor speed reaches apredetermined value, and a circuit closer for closing a circuit in shuntto said speed responsive device to render it ineffective to open saidcircuits after a predetermined movement of said valve means.

23. In combination, an engine, valve means, manually operated meansconnected to said valve means for positioning it, a motor connected tosaid valve means for positioning it, an automatic control deviceresponsive to a force which is a measure of engine power output, meansconnecting said control device to said motor including means responsiveto motor speed for rendering said connecting means ineflective when themotor speed reaches a predetermined value, and means actuated bymovement of said valve means by either said manually operated means orsaid motor for rendering ineil'ective said motor speed responsive means.

24. In combination. controlling the power shaft connected to the lever,means connecting an engine, valve means output of the engine, a valvemeans, a floating it to said shaft, a manual control means and anelectric motor each connected to the floating lever for moving it toposition said valve means, an automataic control device responsive to aforce which is a measure of engine power output, electric circuitsconnectins the automatic control device to said motor, motor speedoperated contact means in said electric circuits for disrupting saidelectric circuits when the motor speed reaches a predetermined value,and contact means'actuated by movement of said shaft for rendering saidmotor speed operated contact means ineffective.

25. In combination, an engine, valve means controlling the power outputof the engine. a shaft connected to the valve means, a floating lever,means connecting it to said shaft, a manual control means and anelectric motor each connected to the floating lever for moving it toposition said valve means, an automatic control device responsive to aforce which is a measure of engine power output, electric circuitsconnecting the automatic control device to said motor, motor speedoperated contact means in said electric circuits for disrupting saidelectric circuits when the motor speed reaches a predetermined value,

contact means actuated by movement of said shaft for rendering saidmotor speed operated contact means ineffective, and means connected tothe manual control means for adjusting the setting of saidautomaticcontrol device.

26. In combination, an engine, a turbosupercharger for the engine, valvemeans for regulating the speed of the turbosupercharger, an automaticcontrol device responsive to a control force which is a measure ofengine power output connected to said valve means for positioning it inresponse to changes in the value of said control force, means foradjusting the setting of said automatic control device, means forlimiting an extreme value of said control force, means for limiting thespeed of the turbosupercharger, and

means operable from a distance for changing the values of the limitsheld by said two limiting means.

27. In combination, an engine, valve means for regulating the engine, amanually operated lever connected to said valve means, a superchargerfor the engine, speed regulating means for the supercharger, anautomatic control device responsive to a force which is a measure ofengine power output, means connected with said manually operated leverfor adjusting the setting of said automatic control device, and meanswhereby said automatic control device may be connected to control eitherthe supercharger regulating means alone or both the superchargerregulating means and said valve means.

28. In combination, an engine, valve means for regulating the engine, amanually operated lever connected to said valve means, a superchargerfor the engine, speed regulating means for the supercharger, anautomatic control device responsive to a force which is a measure ofengine power output, means connected with said manually operated leverfor adjusting the setting of said automatic control device, meansconnecting said automatic control device to said valve means and to saidsupercharger speed regulating means for operating them in sequence, andmeans for disconnecting said valve means from said automatic controldevice.

29. In combination, an engine, valve means which is adapted to vary thepower output of the engine, a control lever for positioning said valvemeans manually, an electric motor, means apt-races including anelectrically operated clutch for connecting the motor to the valvemeans, a supercharger for the engine. a control valve for thesuperchargen'an electric motor. means including an electrically operatedclutch for connecting it to the supercharger control valve, an a.uto-

matic control device which is responsive to a control force which is ameasure ofengine power output, electric circuit means between thecontrol device and said electric motors, and switch means which closessaid circuit means and effects operation of said clutches to connect themotors to said valve means.

30. In combination, an engine. valve means which is adjusted tov varythe power output of the engine, a control lever for positioning said\valve means manually, an electric motor, means including anelectrically operated clutch forconnecting the motor to the valve means,a supercharger for the engine, a control valve for the supercharger, anelectric motor, means including an electrically operated clutch forconnecting it to the supercharger control valve, an automatic controldevice which is responsive to a control force which is a measure ofengine power output, electric circuit means between the control deviceand said electric motors, switch means which closes said circuit meansand effects operation of said clutches to connect the'motors closer toeffect release of said propeller governor.

32.15. control system for aircraft having an engine, a propeller drivenby said engine, a propeller governor for governing the speed of theengine and a throttle valve for controlling the power output of theengine, said system comprising a. manually operated control device, afirst linkage interconnecting said control device and said governor anda second linkage interconnecting said control device and said throttlevalve whereby the setting of'the governor and throttle valve may beadjusted simultaneously by actuation of said control device, ayieldingconnection interposed in said first linkage and means for locking saidgovernor whereby said throttle valve may be adjusted independently bysaid control device after the governor is locked.

33. Apparatus for controlling the pressure of the air supplied to theintake manifold of an internal combustion engine having a throttle, acompressor for supplying air to said intake manifold through saidthrottle, and means for controlling the compression ratio of saidcompressor,

30 Name Date Hallord Oct. 8, 1940 Ammann Aug. 14, 1941 Bugatti Apr. 14,1942 Marples et 2.1. June 2, 1942 Muller Sept. 29, 1942 Muller Dec. 22,1942 Oswald Dec. 22, 1942 Crane et a1. Feb. 23, 1943 Halford et 51. Apr.18, 1944 Truesdell Sept. 19, 1944 Thompson Jan. 30, 1945 Btieglltz Sept.4, 1945 Blaylock Oct. 9, 1945 01mm crs sex. No. 363,192, Lorenzen (A P.c.) pub.

to place said second motor menu under eon- Number trol of said device.2,217,864 CHARLES H. RIDGLEY. 2,228,239 HERBERT H. ANDERSEN. 2,279,615FRANCIS w. 'IBUEBDELL. 3 2,295,344

2.297.235 REFERENCES CITED 2 5310 The following references are or record111 the 2506377 me of this patent: gag-3:: UNITED s'rA'rm mm'rs 1 81363Number Name Date 1 1,557,793 Berger et a] Oct. 20, 1925 2,384,3581,887,146 Conkling Nov. 6, 199: 1,951,927 Dodson 1421220, 1924 11,995,800 Dodson 1hr. 28, 1935 2,079,958 Dodson in; 11, 1927 2,168,958Uchtemtein Ana. 6, 1669 m! 2,205,354 Greu et a1. June 18. 1940 I I jDlsclalmer ,2,476,063.-0harles H. Ridgley, Marblehead, andHerbert H.Andersen, Beverly, Mass., and Francis W. Truesdell, Schenectady, N. Y.CONTROL Sm'mcmem INTERNAL-COMBUSTION ENGINES. Patent dated July 12,1949. Disclaimer filed Nov. 14, 1952, by the assignee, General ElectricCompany.

Hereby enters thls disclaimer to claims 1 and 2 of said patent.

[Oficial "Gazette-December 16,1952]

